The purpose of this study is to determine the short-term effects of hormone replacement therapy (HRT) on cardiac risk factors in post-menopausal women with type 2 diabetes mellitus. Fifty women will participate in this double-blind, randomized, placebo-controlled clinical trial comparing three months of cyclic HRT (conjugated equine estrogen 0.625 mg po QD with 200 mg po QD micronized progesterone days 1-12 of each month) with placebo. Effects on glucose control, lipid profile, clotting factors and endothelial function will be measured.